Here are a bunch of tailing loops for you to look at, and there are a few ok loops in there too for comparison (I wouldn't call 'em sexyloops , but they're ok for a speycaster).

The first clip shows a good cast or two followed by a whole bunch of tails made in a bunch of different ways, then back to a good cast:

tailing loops pt 1 (and bonus marks for anyone who can identify the other casting fault early on in the clip)

If you watch carefully you can see the tails forming at different places as the forward loop rolls out. Some of them I made by applying the power too early, some by applying too much power late in the cast ("punching it"), some by misapplying the power 1/2 way through the stroke, etc. I just went crazy and did a whole bunch of 'em.

The next clip shows the arm motions that cause tailing loops. You can see that the good casts have a longer, smoother stroke, while the tails have short, choppy, or jerky casting motions:

The last clip shows tails made while double hauling. I really cranked on the haul (both forward and back) for these casts, as well as shortened my stroke and really whomped the rod with too much power. Then I made one good one to end things off: